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Physical or mental stress leads to neuroplasticity in the brain and increases the risk of depression and anxiety. Stress exposure causes the dysfunction of peripheral T lymphocytes. However, the pathological role and underlying regulatory mechanism of peripheral T lymphocytes in mood disorders have not been well established. Here, we show that the lack of CD4+ T cells protects mice from stress-induced anxiety-like behavior. Physical stress-induced leukotriene B4 triggers severe mitochondrial fission in CD4+ T cells, which further leads to a variety of behavioral abnormalities including anxiety, depression, and social disorders. Metabolomic profiles and single-cell transcriptome reveal that CD4+ T cell-derived xanthine acts on oligodendrocytes in the left amygdala via adenosine receptor A1. Mitochondrial fission promotes the de novo synthesis of purine via interferon regulatory factor 1 accumulation in CD4+ T cells. Our study implicates a critical link between a purine metabolic disorder in CD4+ T cells and stress-driven anxiety-like behavior.
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Ansiedade/metabolismo , Comportamento Animal/fisiologia , Encefalopatias Metabólicas/metabolismo , Estresse Psicológico/metabolismo , Tonsila do Cerebelo/metabolismo , Tonsila do Cerebelo/patologia , Animais , Ansiedade/genética , Ansiedade/imunologia , Ansiedade/fisiopatologia , Encefalopatias Metabólicas/genética , Encefalopatias Metabólicas/fisiopatologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Modelos Animais de Doenças , Humanos , Camundongos , Dinâmica Mitocondrial/genética , Oligodendroglia/metabolismo , Oligodendroglia/patologia , Análise de Célula Única , Estresse Psicológico/genética , Estresse Psicológico/fisiopatologia , Transcriptoma/genética , Xantina/metabolismoRESUMO
Transforming growth factor-ß (TGF-ß) and Hippo signaling are two critical pathways engaged in cancer progression by regulating both oncogenes and tumor suppressors, yet how the two pathways coordinately exert their functions in the development of hepatocellular carcinoma (HCC) remains elusive. In this study, we firstly conducted an integrated analysis of public liver cancer databases and our experimental TGF-ß target genes, identifying CYR61 as a pivotal candidate gene relating to HCC development. The expression of CYR61 is downregulated in clinical HCC tissues and cell lines than that in the normal counterparts. Evidence revealed that CYR61 is a direct target gene of TGF-ß in liver cancer cells. In addition, TGF-ß-stimulated Smad2/3 and the Hippo pathway downstream effectors YAP and TEAD4 can form a protein complex on the promoter of CYR61, thereby activating the promoter activity and stimulating CYR61 gene transcription in a collaborative manner. Functionally, depletion of CYR61 enhanced TGF-ß- or YAP-mediated growth and migration of liver cancer cells. Consistently, ectopic expression of CYR61 was capable of impeding TGF-ß- or YAP-induced malignant transformation of HCC cells in vitro and attenuating HCC xenograft growth in nude mice. Finally, transcriptomic analysis indicates that CYR61 can elicit an antitumor program in liver cancer cells. Together, these results add new evidence for the crosstalk between TGF-ß and Hippo signaling and unveil an important tumor suppressor function of CYR61 in liver cancer.
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Carcinoma Hepatocelular , Proteína Rica em Cisteína 61 , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas , Fator de Crescimento Transformador beta , Proteínas de Sinalização YAP , Animais , Humanos , Camundongos , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Movimento Celular , Proteína Rica em Cisteína 61/metabolismo , Proteína Rica em Cisteína 61/genética , Mineração de Dados , Regulação Neoplásica da Expressão Gênica/genética , Via de Sinalização Hippo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/genética , Camundongos Nus , Regiões Promotoras Genéticas , Transdução de Sinais/genética , Proteína Smad2/metabolismo , Proteína Smad2/genética , Proteína Smad3/metabolismo , Proteína Smad3/genética , Fatores de Transcrição de Domínio TEA/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta/genética , Regulação para Cima , Proteínas de Sinalização YAP/metabolismo , Proteínas de Sinalização YAP/genéticaRESUMO
Vascular calcification is an actively regulated biological process resembling bone formation, and osteogenic differentiation of vascular smooth muscle cells (VSMCs) plays a crucial role in this process. 1-Palmitoyl-2-(5'-oxo-valeroyl)-sn-glycero-3-phosphocholine (POVPC), an oxidized phospholipid, is found in atherosclerotic plaques and has been shown to induce oxidative stress. However, the effects of POVPC on osteogenic differentiation and calcification of VSMCs have yet to be studied. In the present study, we investigated the role of POVPC in vascular calcification using in vitro and ex vivo models. POVPC increased mineralization of VSMCs and arterial rings, as shown by alizarin red staining. In addition, POVPC treatment increased expression of osteogenic markers Runx2 and BMP2, indicating that POVPC promotes osteogenic transition of VSMCs. Moreover, POVPC increased oxidative stress and impaired mitochondria function of VSMCs, as shown by increased ROS levels, impairment of mitochondrial membrane potential, and decreased ATP levels. Notably, ferroptosis triggered by POVPC was confirmed by increased levels of intracellular ROS, lipid ROS, and MDA, which were decreased by ferrostatin-1, a ferroptosis inhibitor. Furthermore, ferrostatin-1 attenuated POVPC-induced calcification of VSMCs. Taken together, our study for the first time demonstrates that POVPC promotes vascular calcification via activation of VSMC ferroptosis. Reducing the levels of POVPC or inhibiting ferroptosis might provide a novel strategy to treat vascular calcification.
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Cicloexilaminas , Ferroptose , Fenilenodiaminas , Calcificação Vascular , Humanos , Músculo Liso Vascular/metabolismo , Fosfolipídeos/metabolismo , Fosforilcolina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Osteogênese , Calcificação Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Células CultivadasRESUMO
Interferon regulatory factor (IRF) 3 and IRF7 are master regulators of type I interferon (IFN-I)-dependent antiviral innate immunity. Upon viral infection, a positive feedback loop is formed, wherein IRF7 promotes further induction of IFN-I in the later stage. Thus, it is critical to maintain a suitably low level of IRF7 to avoid the hyperproduction of IFN-I. In this study, we find that early expression of IFN-I-dependent STAT1 promotes the expression of XAF1 and that XAF1 is associated specifically with IRF7 and inhibits the activity of XIAP. XAF1-knockout and XIAP-transgenic mice display resistance to viral infection, and this resistance is accompanied by increases in IFN-I production and IRF7 stability. Mechanistically, we find that the XAF1-XIAP axis controls the activity of KLHL22, an adaptor of the BTB-CUL3-RBX1 E3 ligase complex through a ubiquitin-dependent pathway. CUL3-KLHL22 directly targets IRF7 and catalyzes its K48-linked ubiquitination and proteasomal degradation. These findings reveal unexpected functions of the XAF1-XIAP axis and KLHL22 in the regulation of IRF7 stability and highlight an important target for antiviral innate immunity.
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Interferon Tipo I , Viroses , Camundongos , Animais , Viroses/genética , Antivirais , Imunidade Inata , Ubiquitinação , Fator Regulador 7 de Interferon/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Reguladoras de ApoptoseRESUMO
This project addresses the urgent need for efficient and cost-effective development of electrocatalysts for the ethanol oxidation reaction (EOR). This reaction offers promising renewable energy solutions but faces challenges due to the slow EOR kinetics, typically requiring costly noble metal catalysts. To overcome these limitations, this study focuses on developing CuZn-based EOR catalysts derived from metal-organic frameworks (MOFs), focusing on understanding the structure-performance relationship between pristine MOF-based electrocatalysts and their pyrolyzed counterparts. Herein, bimetallic MOF materials with varying Cu/Zn ratios were synthesized, followed by pyrolysis to produce carbonized counterparts while preserving the fundamental structure but with altered physicochemical properties. Comparative EOR studies revealed the superior performance of pyrolyzed MOFs, demonstrating that optimized Zn-loading is crucial over Cu-based framework for catalyst performance and durability. Overall, this work highlights the potential of MOF-derived Cu-based catalysts for renewable energy applications and provides insights into optimizing their performance through controlled synthesis and post-treatment strategies.
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Osteoporosis is particularly prevalent among postmenopausal women and the elderly. In the present study, we investigated the effect of the novel small molecule E0924G (N-(4-methoxy-pyridine-2-yl)-5-methylfuran-2-formamide) on osteoporosis. E0924G significantly increased the protein expression levels of osteoprotegerin (OPG) and runt-related transcription factor 2 (RUNX2), and thus significantly promoted osteogenesis in MC3T3-E1 cells. E0924G also significantly decreased osteoclast differentiation and inhibited bone resorption and F-actin ring formation in receptor activator of NF-κB ligand (RANKL)-induced osteoclasts from RAW264.7 macrophages. Importantly, oral administration of E0924G in both ovariectomized (OVX) rats and SAMP6 senile mice significantly increased bone mineral density and decreased bone loss compared to OVX controls or SAMR1 mice. Further mechanistic studies showed that E0924G could bind to and then activate peroxisome proliferator-activated receptor delta (PPARδ), and the pro-osteoblast effect and the inhibition of osteoclast differentiation induced by E0924G were significantly abolished when PPARδ was knocked down or inhibited. In conclusion, these data strongly suggest that E0924G has the potential to prevent OVX-induced and age-related osteoporosis by dual regulation of bone formation and bone resorption through activation of the PPARδ signaling pathway.
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Reabsorção Óssea , Osteogênese , Ovariectomia , PPAR delta , Transdução de Sinais , Animais , Camundongos , Reabsorção Óssea/tratamento farmacológico , Reabsorção Óssea/prevenção & controle , Reabsorção Óssea/metabolismo , Ratos , PPAR delta/metabolismo , Feminino , Osteogênese/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade , Estrutura Molecular , Células RAW 264.7 , Osteoporose/tratamento farmacológico , Osteoporose/prevenção & controle , Osteoporose/metabolismo , Relação Dose-Resposta a Droga , Bibliotecas de Moléculas Pequenas/farmacologia , Bibliotecas de Moléculas Pequenas/química , Ratos Sprague-Dawley , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Diferenciação Celular/efeitos dos fármacosRESUMO
Proprotein convertase subtilisin/kexin type 9 (PCSK9) binds to the epidermal growth factor precursor homologous domain A (EGF-A) of low-density lipoprotein receptor (LDLR) in the liver and triggers the degradation of LDLR via the lysosomal pathway, consequently leading to an elevation in plasma LDL-C levels. Inhibiting PCSK9 prolongs the lifespan of LDLR and maintains cholesterol homeostasis in the body. Thus, PCSK9 is an innovative pharmacological target for treating hypercholesterolemia and atherosclerosis. In this study, we discovered that E28362 was a novel small-molecule PCSK9 inhibitor by conducting a virtual screening of a library containing 40,000 compounds. E28362 (5, 10, 20 µM) dose-dependently increased the protein levels of LDLR in both total protein and the membrane fraction in both HepG2 and AML12 cells, and enhanced the uptake of DiI-LDL in AML12 cells. MTT assay showed that E28362 up to 80 µM had no obvious toxicity in HepG2, AML12, and HEK293a cells. The effects of E28362 on hyperlipidemia and atherosclerosis were evaluated in three different animal models. In high-fat diet-fed golden hamsters, administration of E28362 (6.7, 20, 60 mg·kg-1·d-1, i.g.) for 4 weeks significantly reduced plasma total cholesterol (TC), triglyceride (TG), low-density lipoprotein-cholesterol (LDL-C) and PCSK9 levels, and reduced liver TC and TG contents. In Western diet-fed ApoE-/- mice (20, 60 mg·kg-1·d-1, i.g.) and human PCSK9 D374Y overexpression mice (60 mg·kg-1·d-1, i.g.), administration of E28362 for 12 weeks significantly decreased plasma LDL-C levels and the area of atherosclerotic lesions in en face aortas and aortic roots. Moreover, E28362 significantly increased the protein expression level of LDLR in the liver. We revealed that E28362 selectively bound to PCSK9 in HepG2 and AML12 cells, blocked the interaction between LDLR and PCSK9, and induced the degradation of PCSK9 through the ubiquitin-proteasome pathway, which finally resulted in increased LDLR protein levels. In conclusion, E28362 can block the interaction between PCSK9 and LDLR, induce the degradation of PCSK9, increase LDLR protein levels, and alleviate hyperlipidemia and atherosclerosis in three distinct animal models, suggesting that E28362 is a promising lead compound for the treatment of hyperlipidemia and atherosclerosis.
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Molybdenum (Mo) is a rare and important element extensively utilised in aerospace, radar communications, optoelectronic devices, and the military. This study proposes an environmentally friendly physical method based on photon-phonon resonance absorption for the separation of Mo from sodium molybdate (Na2MoO4). We examined the vibrational spectrum of Na2MoO4 using the CASTEP code, employing first-principles density functional theory. Through dynamic process analysis, we analysed the vibrational modes and assigned peaks corresponding to experimental infrared (IR) and Raman data. We focused on the vibrational modes associated with Mo and identified that the highest-intensity IR-active peak at 858 cm-1 corresponded to Mo-O bond asymmetric stretching. Therefore, we propose the use of a high-power terahertz laser at ~25 THz to facilitate the separation of Mo from Na2MoO4. Experimental investigations are expected in the future.
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OBJECTIVE: To investigate the association of leisure-time physical activity and serum cotinine levels with the risk of periodontitis in the general population and to further analyze the interaction between leisure-time physical activity and serum cotinine levels on the risk of periodontitis. METHODS: This was a cross-sectional study, extracting data from 9605 (56.19%) participants in the National Health and Nutrition Examination Survey (NHANES) database from 2009 to 2014, and analyzing the relationship and interaction effects of serum cotinine level, leisure time physical activity, and risk of periodontitis by weighted univariate logistic modeling; Effect sizes were determined using ratio of ratios (OR), 95% confidence intervals (95% CI). RESULTS: 5,397 (56.19%) of 9,605 participants had periodontitis; an increased risk of periodontitis was found in those in the leisure time physical activity intensity < 750 MET × min/week group (OR = 1.44, 95% CI: 1.17-1.78). Serum cotinine levels ≥ 0.05 ng/ml were associated with an increased risk of periodontitis (OR = 1.99, 95% CI: 1.69-2.33). The group with low leisure physical activity and serum cotinine levels ≥ 0.05 ng/ml had an increased risk of periodontitis compared to the group with high leisure physical activity and serum cotinine levels < 0.05 ng/ml (OR = 2.48, 95% CI: 1.88-3.27). Interaction metrics RERI = 0.90 (95% CI: 0.44-1.36) and API = 0.36 (95% CI: 0.18-0.55); CI for SI = 2.55 (95% CI: 1.03-6.28). for API 0.36. CONCLUSION: Leisure time physical activity intensity interacted with smoking exposure on periodontitis risk and may provide the general population with the opportunity to Increasing leisure-time physical activity and smoking cessation may provide recommendations for the general population.
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Periodontite , Poluição por Fumaça de Tabaco , Humanos , Cotinina/análise , Fumar/efeitos adversos , Poluição por Fumaça de Tabaco/efeitos adversos , Inquéritos Nutricionais , Estudos Transversais , Periodontite/epidemiologia , Exercício Físico , Atividades de LazerRESUMO
Nonalcoholic fatty liver disease (NAFLD) is one of the most common liver diseases. Silencing information regulator 1 (SIRT1) was demonstrated to modulate cholesterol and lipid metabolism in NAFLD. Here, a novel SIRT1 activator, E1231, was studied for its potential improvement effects on NAFLD. C57BL/6J mice were fed a high-fat and high-cholesterol diet (HFHC) for 40 weeks to create a NAFLD mouse model, and E1231 was administered by oral gavage (50 mg/kg body weight, once/day) for 4 weeks. Liver-related plasma biochemistry parameter tests, Oil Red O staining, and hematoxylin-eosin staining results showed that E1231 treatment ameliorated plasma dyslipidemia, plasma marker levels of liver damage (alanine aminotransferase (ALT) and aspartate aminotransferase (AST)), liver total cholesterol (TC) and triglycerides (TG) contents, and obviously decreased hepatic steatosis score and NAFLD Activity Score (NAS) in the NAFLD mouse model. Western blot results showed that E1231 treatment significantly regulated lipid-metabolism-related protein expression. In particular, E1231 treatment increased SIRT1, PGC-1α, and p-AMPKα protein expression but decreased ACC and SCD-1 protein expression. Additionally, in vitro studies demonstrated that E1231 inhibited lipid accumulation and improved mitochondrial function in free-fatty-acid-challenged hepatocytes, and required SIRT1 activation. In conclusion, this study illustrated that the SIRT1 activator E1231 alleviated HFHC-induced NAFLD development and improved liver injury by regulating the SIRT1-AMPKα pathway, and might be a promising candidate compound for NAFLD treatment.
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PURPOSE: The goal of this study is to evaluate the efficacy and safety of modified triangular double-J (DJ) stent in 1-2 cm renal or ureter calculi after retrograde intrarenal surgery (RIRS) via a randomized, controlled clinical study. METHODS: A total of 196 patients with 1-2 cm renal or ureter calculi who were performed RIRS and received 7Fr modified triangular DJ stents (100 cases) or 6Fr normal DJ stents (96 cases). All operations were performed by experienced surgeons. The clinical characteristics and outcomes were analyzed. RESULTS: There were no significant differences between two groups in terms of age, gender, BMI, location, hydronephrosis, urea WBC, urea RBC, BUN, Cr, laser emission time, operation time, Hb loss, postoperative BUN, postoperative Cr. Patients who received modified triangular DJ stents were shown to have higher stone-free rate (p = 0.038), but lower general health (p = 0.004). CONCLUSION: The modified triangular 7Fr DJ stents were more efficient for patients underwent RIRS than 6Fr normal DJ stents.
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Cálculos Renais , Ureter , Ureterolitíase , Humanos , Ureter/cirurgia , Cálculos Renais/cirurgia , Qualidade de Vida , Rim/cirurgia , Stents , Resultado do TratamentoRESUMO
Vascular calcification is an actively regulated process resembling bone formation and contributes to the cardiovascular morbidity and mortality of chronic kidney disease (CKD). However, an effective therapy for vascular calcification is still lacking. The ketone body ß-hydroxybutyrate (BHB) has been demonstrated to have health-promoting effects including anti-inflammation and cardiovascular protective effects. However, whether BHB protects against vascular calcification in CKD remains unclear. In this study, Alizarin Red staining and calcium content assay showed that BHB reduced calcification of vascular smooth muscle cells (VSMCs) and arterial rings. Of note, compared with CKD patients without thoracic calcification, serum BHB levels were lower in CKD patients with thoracic calcification. Supplementation with 1,3-butanediol (1,3-B), the precursor of BHB, attenuated aortic calcification in CKD rats and VitD3-overloaded mice. Furthermore, RNA-seq analysis revealed that BHB downregulated HDAC9, which was further confirmed by RT-qPCR and western blot analysis. Both pharmacological inhibition and knockdown of HDAC9 attenuated calcification of human VSMCs, while overexpression of HDAC9 exacerbated calcification of VSMCs and aortic rings, indicating that HDAC9 promotes vascular calcification under CKD conditions. Of note, BHB treatment antagonized HDAC9-induced vascular calcification. In addition, HDAC9 overexpression activated the NF-κB signaling pathway and inhibition of NF-κB attenuated HDAC9-induced VSMC calcification, suggesting that HDAC9 promotes vascular calcification via activation of NF-κB. In conclusion, our study demonstrates that BHB supplementation inhibits vascular calcification in CKD via modulation of the HDAC9-dependent NF-κB signaling pathway. Moreover, we unveil a crucial mechanistic role of HDAC9 in vascular calcification under CKD conditions; thus, nutritional intervention or pharmacological approaches to enhance BHB levels could act as promising therapeutic strategies to target HDAC9 for the treatment of vascular calcification in CKD. © 2022 The Pathological Society of Great Britain and Ireland.
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Insuficiência Renal Crônica , Calcificação Vascular , Ácido 3-Hidroxibutírico/metabolismo , Animais , Cálcio/metabolismo , Células Cultivadas , Regulação para Baixo , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Humanos , Cetonas/metabolismo , Camundongos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/patologia , NF-kappa B/metabolismo , Ratos , Insuficiência Renal Crônica/patologia , Proteínas Repressoras/metabolismo , Calcificação Vascular/genética , Calcificação Vascular/prevenção & controleRESUMO
OBJECTIVES: Oral squamous cell carcinoma (OSCC) is often diagnosed with cervical lymph node metastasis. Mesenchymal stem cells (MSCs) and interleukin-6 (IL-6) signalling are considered to play important roles in promoting tumour malignancy. The detailed biological interaction of MSCs and IL-6 and the subsequent effect on OSCC metastasis remain largely unclear. This study aimed to determine the effects and molecular mechanism of MSCs-derived IL-6 on tumour invasion and metastasis. SUBJECTS AND METHODS: The effects of MSC-derived IL-6 and tocilizumab on the proliferation, mobility, and epithelial-mesenchymal transition (EMT) of OSCC cells and potential pathways were detected in vitro. In addition, a murine xenograft model was generated to verify the biological mechanism in vivo. RESULTS: The results showed that the expression of MSCs and EMT-related signals was increased in poorly differentiated OSCC tissues. MSCs released a higher level of IL-6 and promoted the proliferation, invasion, and metastasis of OSCC cells and solid neoplasms, which were activated by the downstream molecules JAK and STAT3. CONCLUSIONS: The results indicated that MSCs-derived IL-6-promoted tumour invasion and metastasis via JAK-STAT3 signalling. Blockade of this pathway by tocilizumab may be a potential treatment to improve the prognosis and survival rate of patients with OSCC.
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Cl, Br, and I are elements in the halogen family, and are often used as dopants in semiconductors. When employed as dopants, these halogens can significantly modify the optoelectronic properties of materials. From the perspective of halogen doping, we have successfully achieved the stabilization of crystal structures in CH3NH3PbX3, CH3NH3PbI3-xClx, CH3NH3PbI3-xBrx, and CH3NH3PbBr3-xClx, which are organic-inorganic hybrid perovskites. Utilizing first-principles density functional theory calculations with the CASTEP module, we investigated the optoelectronic properties of these structures by simulations. According to the calculations, a smaller difference in electronegativity between different halogens in doped structures can result in smoother energy bands, especially in CH3NH3PbI3-xBrx and CH3NH3PbBr3-xClx. The PDOS of the Cl-3p orbitals undergoes a shift along the energy axis as a result of variances in electronegativity levels. The optoelectronic performance, carrier mobility, and structural stability of the CH3NH3PbBr3-xClx system are superior to other systems like CH3NH3PbX3. Among many materials considered, CH3NH3PbBr2Cl exhibits higher carrier mobility and a relatively narrower bandgap, making it a more suitable material for the absorption layer in solar cells. This study provides valuable insights into the methodology employed for the selection of specific types, quantities, and positions of halogens for further research on halogen doping.
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The theory of electron spin has been proposed for a century, but the study of quantum effects in biological molecules is still in its infancy. Chirality-induced spin selectivity (CISS) is a very modern theory that can explain many biochemical phenomena. In this paper, we propose a new theoretical model based on CISS theory and quantum chemistry theory, which can well explain the theoretical explanation of the chiral selectivity of chiral proteins. Moreover, this theory can predict the spin state of corresponding chiral molecules. Taking the L-DOPA and AADC enzymes as examples, this theoretical model elucidates the AADC enzyme's chiral catalysis selectivity and successfully predicts the spin state of L-DOPA and D-DOPA's valence electrons.
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Two-dimensional (2D) ice I is atomic-level ice that is composed of two interlocked atomic layers saturated with hydrogen bonds. It has recently been experimentally observed, but its properties have yet to be clarified. Accordingly, we theoretically studied the hydrophobic properties of 2D ice I. On the contrary, a simulation of a hydrogen fluoride molecule on a 2D ice surface manifested that it destroyed the 2D ice structure and connected new hydrogen bonds with water molecules. Investigations of the interfacial effect between 2D and three-dimensional (3D) ice films indicated that the network structure of 2D ice was not destroyed by a 3D ice surface, as the former was saturated with hydrogen bonds. However, the surface of 3D ice reorganized to form as many hydrogen bonds as possible. Thus, the 2D ice film was hydrophobic and inhibited the growth of 3D ice. This shows that if 2D ice can be produced on an industrial scale, it can be used as an anti-3D-icing agent under low temperatures.
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Vascular calcification is an important risk factor for cardiovascular events, accompanied by DNA damage during the process. The sirtuin 6 (SIRT6) has been reported to alleviate atherosclerosis, which is related to the reduction of DNA damage. However, whether smooth muscle cell SIRT6 mediates vascular calcification involving DNA damage remains unclear. Western blot and immunofluorescence revealed that SIRT6 expression was decreased in human vascular smooth muscle cells (HVSMCs), human and mouse arteries during vascular calcification. Alizarin red staining and calcium content assay showed that knockdown or deletion of SIRT6 significantly promoted HVSMC calcification induced by high phosphorus and calcium, accompanied by upregulation of osteogenic differentiation markers including Runx2 and BMP2. By contrast, adenovirus-mediated SIRT6 overexpression attenuated osteogenic differentiation and calcification of HVSMCs. Moreover, ex vivo study revealed that SIRT6 overexpression inhibited calcification of mouse and human arterial rings. Of note, smooth muscle cell-specific knockout of SIRT6 markedly aggravated Vitamin D3-induced aortic calcification in mice. Mechanistically, overexpression of SIRT6 reduced DNA damage and upregulated p-ATM during HVSMCs calcification, whereas knockdown of SIRT6 showed the opposite effects. Knockdown of ATM in HVSMCs abrogated the inhibitory effect of SIRT6 overexpression on calcification and DNA damage. This study for the first time demonstrates that vascular smooth muscle cell-specific deletion of SIRT6 facilitates vascular calcification via suppression of DNA damage repair. Therefore, modulation of SIRT6 and DNA damage repair may represent a therapeutic strategy for vascular calcification.
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Sirtuínas , Calcificação Vascular , Humanos , Cálcio/metabolismo , Dano ao DNA , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Osteogênese/genética , Sirtuínas/genética , Sirtuínas/metabolismo , Calcificação Vascular/genética , Reparo do DNARESUMO
Vascular calcification is a common pathologic condition in patients with chronic kidney disease (CKD). Cell death such as apoptosis plays a critical role in vascular calcification. Ferroptosis is a type of iron-catalyzed and regulated cell death resulting from excessive iron-dependent reactive oxygen species and lipid peroxidation. However, it is unclear whether ferroptosis of vascular smooth muscle cells (VSMCs) regulates vascular calcification in CKD. Our results showed that high calcium and phosphate concentrations induced ferroptosis in rat VSMCs in vitro. Inhibition of ferroptosis by ferrostatin-1 dose-dependently reduced mineral deposition in rat VSMCs under pro-osteogenic conditions, as indicated by alizarin red staining and quantification of calcium content. In addition, gene expression analysis revealed that ferrostatin-1 inhibited osteogenic differentiation of rat VSMCs. Similarly, ferrostatin-1 remarkably attenuated calcification of rat and human arterial rings ex vivo and aortic calcification in vitamin D3-overloaded mice in vivo. Moreover, inhibition of ferroptosis by either ferrostatin-1 or deferoxamine attenuated aortic calcification in rats with CKD. Mechanistically, high calcium and phosphate downregulated expression of SLC7A11 (a cystine-glutamate antiporter), and reduced glutathione (GSH) content in VSMCs. Additionally, GSH depletion induced by erastin (a small molecule initiating ferroptotic cell death) significantly promoted calcification of VSMCs under pro-osteogenic conditions, whereas GSH supplement by N-acetylcysteine reduced calcification of VSMCs. Consistently, knockdown of SLC7A11 by siRNA markedly promoted VSMC calcification. Furthermore, high calcium and phosphate downregulated glutathione peroxidase 4 (GPX4) expression, and reduced glutathione peroxidase activity. Inhibition of GPX4 by RSL3 promoted VSMC calcification. Thus, repression of the SLC7A11/GSH/GPX4 axis triggers ferroptosis of VSMCs to promote vascular calcification under CKD conditions, providing a novel targeting strategy for vascular calcification.
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Ferroptose , Insuficiência Renal Crônica , Calcificação Vascular , Humanos , Ratos , Camundongos , Animais , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Músculo Liso Vascular , Osteogênese , Cálcio/metabolismo , Antiporters/metabolismo , Miócitos de Músculo Liso/metabolismo , Calcificação Vascular/genética , Calcificação Vascular/prevenção & controle , Ferro/metabolismo , Glutationa/metabolismo , Insuficiência Renal Crônica/patologia , Fosfatos/metabolismo , Sistema y+ de Transporte de Aminoácidos/genética , Sistema y+ de Transporte de Aminoácidos/metabolismoRESUMO
BACKGROUND: Molecular etiology of lingual hamartoma is poorly understood. This study aims to identify potentially deleterious mutations for lingual hamartoma and analyze its molecular profile by a combination of whole-exome sequencing and RNA-sequencing. METHODS: Whole-exome sequencing was conducted on the proband presenting lingual hamartoma and patient's unaffected family members. Potentially pathogenic mutations were identified after filtration. The pathogenicity of the identified variants was predicted by in silico algorithms and conservative analysis. RNA-sequencing was performed to further explore the molecular profile of lingual hamartoma. RESULTS: Whole-exome sequencing of the proband and patients' unaffected brother and parents identified a de novo mutation c.931C>T_p.Pro311Ser in the DYNC2H1 gene (NM_001080463.2). The DYNC2H1 mutation was predicted to be disease-causing for affecting highly conserved amino acid by PolyPhen2 and Mutation Taster. RNA-sequencing analysis showed that the DYNC2H1 gene was significantly down-regulated in lingual hamartoma. Gene set enrichment analysis revealed cilium assembly and Hedgehog signaling pathway were significantly affected. CONCLUSION: The study expanded our knowledge on the clinical and genetic spectrum of lingual hamartoma by identifying causal variants in a Chinese pedigree. DYNC2H1 is likely to participate in tongue development and its pathologic mutation may underlie the etiology of lingual hamartoma.
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Hamartoma , Proteínas Hedgehog , China , Dineínas do Citoplasma , Hamartoma/genética , Humanos , Masculino , Linhagem , RNARESUMO
Asymmetric copolymerization of meso-epoxide and anhydride is a powerful strategy for preparing various isotactic polyesters with two contiguous stereogenic centers. However, the previous binary systems suffered from slow rates at low loadings, poor enantioselectivities and transesterification reactions at enhanced temperatures. Herein, we report novel dinuclear aluminium complexes with multiple chiralities and ammonium salts anchored on ligand frameworks. These bifunctional catalysts exhibit high activities and enantioselectivities for epoxides/anhydrides copolymerizations at harsh conditions via intramolecularly synergistic catalysis, affording polyesters with unprecedented molecular weights and narrow distributions. Notably, no transesterification reactions were observed, significantly different from the binary catalyst/cocatalyst pairs. This study represents a rare example regarding temperature-independent asymmetric induction for preparing chiral polymers from achiral monomers.